Fertility History Research Articles

Gender differences in the association between parity and cognitive function: Evidence from the UK biobank

While much previous work linking fertility history with late-life cognition has focused on a narrow set of cognitive measures and/or has used modest sample sizes in the analysis, our paper expands the size and scope of these linkages by analyzing cognitive function across five domains and precisely estimating gendered patterns between men and women. Results point to important gendered associations between parity and cognition: having children is likely associated with better cognitive function for fathers in all five domains. However, mothers show worse cognitive function in some domains (i.e., numeric memory, prospective memory, and fluid intelligence) than childless women. We explore the possibility of confounding in these associations and rule out the effects of genetic cognitive ability on fertility. We also find that adding controls for educational attainment differ by gender—strengthening associations between parity and cognition for men and largely eliminating them for women. The findings support previous work done on how life course contexts may link to the risk of dementia or cognitive impairment, highlighting parity as potential protective or risk factors to parents’ cognitive health. The use of five cognitive domains yields variations in results, giving implications on measure selection of cognitive function and calling for replicated work covering more cognitive domains.

The demographic consequences of sex‐selection technology

Over the last several years, highly accurate methods of sex selection before conception have been developed. Given that strong preferences for sex variety in offspring have been documented for the U.S., we ask what the demographic consequences of sex‐selection technology could be. Lacking variation across space and time in access to this technology, we estimate a dynamic programming model of fertility decisions with microdata on fertility histories. We leverage the quasi‐experimental variation inherent in the random determination of sex to identify the key structural parameter characterizing preferences for sex variety in offspring. We then simulate the introduction of this technology. While this technology can reduce fertility by allowing parents to efficiently reach their preferred sex mix, it could also increase it. This is because without this technology, many parents may opt not to have another baby given the uncertainty about its sex. Results suggest that these two effects operate simultaneously, but on net, sex‐selection technology ends up reducing the average family size among married women by less than 2% in the steady state, a much smaller decline than the one that would be predicted by alternative methods.

Divergent responses of soil microorganisms to throughfall exclusion across tropical forest soils driven by soil fertility and climate history

Model projections predict tropical forests will experience longer periods of drought and more intense precipitation cycles under a changing climate. Such transitions have implications for structure-function relationships within microbial communities. We examine how throughfall exclusion might reshape prokaryotic and fungal communities across four lowland forests in Panama with a wide variation in mean annual precipitation and soil fertility. Four sites were established across a 1000 mm span in Mean Annual Precipitation (MAP: 2335–3421 mm). We expected microbial communities at sites with lower MAP to be less sensitive to throughfall exclusion than sites with higher MAP and fungal communities to be more resistant to disturbance than prokaryotes. At each location, partial throughfall exclusion structures were established over 10 × 10 m plots to reduce direct precipitation input. After short-term (∼3–9 months) throughfall exclusion, prokaryotic communities showed no change in composition. However, prolonged (12–18 months) throughfall exclusion resulted in divergent prokaryotic community responses, reflecting MAP and soil fertility. We observed the emergence of a “drought microbiome” within infertile sites, whereby the community structure of the experimental throughfall exclusion plots at the lower MAP sites diverged from their respective control sites and converged towards overlapping assemblages. Furthermore, under throughfall exclusion, taxa increasing in relative abundance at the wettest site reflected that endemic to control plots at the lowest MAP site, suggesting a shift toward communities with life-history traits selected for under a lower MAP. By contrast, fungal community composition across sites was resilient to throughfall exclusion; however, biomass diverged in response to throughfall exclusion, increasing at two sites while decreasing in the other two. Broadly, our results suggest that microbial communities' sensitivity to frequent drying and rewetting periods in tropical forest soils will depend on climate history and soil fertility, with infertile sites likely to respond readily to changes in precipitation.

Frozen embryo transfer in the menstrual cycle after moderate-severe ovarian hyperstimulation syndrome: a retrospective analysis

BackgroundOvarian hyperstimulation syndrome (OHSS) is a rare but serious complication of controlled ovarian stimulation. Frozen-embryo transfer (ET) is prompted to be performed in the next menstrual cycles after cancellation of fresh-ET after occurrence of OHSS. However, effects of frozen-ET in the second menstrual cycle have never been investigated. Therefore, this study aimed to assess this in the menstrual cycle after OHSS.MethodsThe OHSS group included 342 women with moderate-severe OHSS who underwent the first frozen-ET in the second menstrual cycle in the First Affiliated Hospital of Anhui Medical University from June 2018 to September 2019. A total of 342 women without OHSS who received frozen-ET in the second menstrual cycle were selected as control group matched by age, body mass index, fertility history, ovulation induction scheme. Uni- and multi-variable conditional logistic regression was used to estimate the association between moderate-severe OHSS and pregnancy outcomes.ResultsThere were no significant differences in maternal outcomes (miscarriage, preterm birth and pregnancy complications including gestational diabetes mellitus, pregnancy-induced hypertension, placenta previa, premature rupture of membranes and postpartum hemorrhage) and in neonatal outcome (birth-weight and body length, neonatal congenital diseases and other complications) between the two groups in either uni- or multi-variable models.ConclusionsFrozen-ET in the menstrual cycle after OHSS has similar maternal and neonatal outcomes as in women without OHSS. This study indicates that frozen-ET could be performed in the second menstrual cycle in women who recovered from moderate-severe OHSS.

Role of the Q36R polymorphism in the KISS1 gene in female infertility

BackgroundInfertility has evolved into a worldwide reproductive health concern that is distinctively constituted within various socio-cultural contexts. Female infertility is a global health concern ailment in couples who have been unable to conceive for a year. Kisspeptin (KISS1) is a peptide hormone that is important in women's health difficulties such as infertility. Based on previous studies, single nucleotide polymorphisms (SNPs) in KISS1 gene can be a cause for infertility. The objective of this study is to explore into the Q36R SNP in the KISS1 gene in Saudi infertile women. MethodsIn this case-control study, 96 cases of female infertile and 96 control women was selected. Deoxyribonucleic acid (DNA) was extracted to perform polymerase chain reaction and followed by restriction fragment length polymorphism analysis. All DNA products were run on 2% agarose and obtained data was imported into excel to perform the statistical analysis using SPSS software between cases and controls. ResultsThe anthropometric analysis (p > 0.05), genotype (OR-3.60; 95 %CI:0.96–13.55; p = 0.04), allele (OR-2.49; 95 %CI: 0.86–7.21; p = 0.08) and different genetic models (AG + GG vs AA; OR-1.00; 95 %CI: 0.01–7.02; p = 0.005) showed negative association and fertility histories showed significant association (p < 0.0001). Anova analysis showed the positive association with weight (p = 0.01) and BMI (p = 0.003). ConclusionThis study found no connection between the Q36R SNP in the KISS1 gene and female infertility in Saudi Arabia.

Nitrogen fertilization value of compost and dried dung in soils with contrasting synthetic nitrogen fertilization histories

AbstractIf the production of forage for dairy cattle is to become less reliant on synthetic nitrogen (N) fertilizers, there is need to better understand and account for the N contributed by on‐farm and imported organic amendments. A 254‐day aerobic soil incubation study (typical length of a growing season in many temperate dairying regions) quantified the inorganic (mineral) N supply from a commercial compost and dried bovine dung (i.e., on‐farm effluent solids). Amendments were incubated in soils with contrasting synthetic N fertilization histories (i.e., 70–100 vs. 350–400 kg N/ha per year) to evaluate if higher synthetic N fertilization histories would reduce the lag time that often exists between organic amendment application and significant release of inorganic N for plant uptake. This proposition was based on previous research, which showed greater soil inorganic N availability accelerating organic amendment decomposition. Our experiment did find that the release of inorganic N from evaluated organic amendments was greater in soils with higher synthetic N fertilization histories, but that this effect was not apparent until after the first 6‐months of this 9‐month experiment. Despite this finding, soils with contrasting synthetic N fertilization histories were not found to differ in their initial inorganic N content, nor microbial activity or other physiochemical properties known to affect N mineralization. Our study highlighted the long‐term vision needed when transitioning from synthetic N fertilizers to organic amendments, with most of the N present in the compost and dried dung remaining unavailable for forage production (i.e., remained bound in organic carbon‐based molecules).

Evolutionary history and patterns of geographical variation, fertility, and hybridization in Stuckenia (Potamogetonaceae).

Aquatic plant species are often widespread, even across continents. They pose a challenge to species delimitation and taxonomy due to their reduced morphology and high phenotypic plasticity. These difficulties are even more pronounced in the case of interspecific hybridization. We investigate the aquatic plant genus Stuckenia for the first time on a worldwide scale. Expert species determination is aided by sequencing of nuclear ribosomal ITS and 5S-NTS regions and the plastid intergenic spacers rpl20-5'rps12 and trnT-trnL. Nuclear markers are used to infer hybridization, and the maternal origin of hybrids is addressed with plastid markers. Pure species are subjected to phylogenetic analyses. Two main Stuckenia lineages are found: one consists of S. amblyphylla, S. filiformis, S. pamirica, and S. vaginata, the other includes S. pectinata and S. striata. The widespread species S. pectinata, S. filiformis, and S. vaginata show intraspecific genetic variation, which is structured geographically. Many intraspecific hybrids, which are usually fertile, occur between those genotypes. Interspecific hybrids, which are consistently sterile, are detected among all widespread species; some are reported for the first time in several countries and regions. They originated multiple times from reciprocal crosses and reflect the geographical origins of parental genotypes. Intraspecific genetic variation can be higher than interspecific differences between closely related species. Comparison of phenotypic variation in the field and in cultivation with genotypic variation shows that numerous conspicuous forms have been overestimated taxonomically. These are resolved as phenotypes responding to unusual environments, have recurrently evolved adaptations, or represent extreme forms of continuous variation of the recognized species. However, some specific regional lineages, which have evolved from variable species, may be interpreted as early steps of the speciation process. Hybridization has been underestimated in some regions as a source of Stuckenia diversity, and the respective hybrid plants have been misidentified as intraspecific taxa or even as separate species. Many erroneous entries in sequence databases are detected and summarized. This work provides a sound basis for species delimitation and hybrid recognition in this difficult genus.

Investigating the application of generalized additive models to discrete-time event history analysis for birth events

Discrete-time event history analysis (EHA) is the standard approach taken when modelling fertility histories collected in surveys, where the date of birth is often recorded imprecisely. This method is commonly used to investigate the factors associated wit

Disease Eradication, Infant Mortality, and Fertility Response: Evidence from Malaria Eradication in India

Using a massive malaria eradication program in India during the 1950s as a natural experiment, we examine the effects of disease environment on child health outcomes and fertility. We harmonise a rich dataset on malaria endemicity with fertility histories of women to exploit the cohort level variation in exposure to the program. We find that the program leads to a significant decline in infant and neonatal mortality and leads to a significant increase in the probability of birth during adolescent years in high malaria endemic regions. We confirm that a fall in the mother’s age at first birth in the post-eradication period drives the fertility response.

Assessment of Clinical Features Responsible for Ectopic Pregnancy

Background: Ectopic pregnancy is a lethal condition and a gynecological emergency. It is associated with maternal morbidity and mortality with pregnancy loss. The incidence of ectopic pregnancy is increasing worldwide. The diagnosis of the ectopic pregnancy can be difficult without the suspicion of the condition. It is confused with the pelvic inflammatory disease and miscarriage. Objective: This study may help on formulating a guiding principle on the diagnosis and management of Ectopic pregnancies in this area. In this research the frequency of clinical presentations and factors responsible for ectopic pregnancy are determined. Methodology: This is a cross-sectional based study. This study was conducted at the Obstetricians and gynecology department of Murshid Hospital and health care Center Karachi. The 125 women diagnosed with ectopic pregnancy for the duration of six months from July 2021 to December 2021were included. Patients were examined for outcome variables (abdominal pain, vaginal bleeding, history of infertility, use of IUCD and previous ectopic pregnancy) noted in predesigned performa. Results: - The women mean age was 9m31 ± 6.6 years. There were 96 (78.4%) women observed with abdominal pain and 72 (57.6%) women with vaginal bleeding in which some of them had both clinical presentations. History of fertility 34 (27.2%), use of intrauterine contraceptive device 58 (46.4%) and previous ectopic pregnancy 33 (26.4%) were responsible for ectopic pregnancy. Conclusion: Majority of the patients attended the hospital were in acute condition. They were diagnosed with classical features of ruptured ectopic pregnancy. The most common clinical features were use of IUD, infertility history, and previous ectopic pregnancy. . For reducing the morbidity and mortality rates associated with the ectopic pregnancy the early diagnosis of the tubal rupture is an essential factor. Keywords: Ectopic pregnancy, vaginal bleeding, intrauterine contraceptive device

Efficacy of Calcium Chloride Dihydrate Supplementation at ICSI on Patient Outcomes

Background: ICSI typically results in fertilisation rates of &gt;65% however patients may still have low or no fertilisation despite the oocyte and sperm quality appearing normal. After entry of the sperm into the oocyte, a cascade of reactions facilitates calcium release and subsequent oocyte activation. In cases of poor or failed fertilisation it is possible that this cascade fails and therefore different methods of artificial oocyte activation are used to try and induce calcium release. Aim: To determine if calcium chloride dihydrate supplementation in the PVP (5mM) at the time of ICSI (ICSI-Ca) improves fertilisation, utilisation and clinical pregnancy rates compared to ICSI alone, particularly in patients with a history of low fertilisation (&lt;50%). Methods: Retrospective study between 2016-2021 at Monash IVF Victoria on a paired cohort of patients (n=178 patients) where an ICSI cycle was analysed coupled with the subsequent ICSI-Ca cycle. The paired cohort was further subdivided into a low-fertilisation cohort (&lt;50% fertilisation on previous cycles: n=66 patients) compared to the remaining patients with normal-fertilisation ([Formula: see text] 50%; n=122). Exclusion criteria included donor cycles, PGT patients, surgical sperm retrieval, women [Formula: see text] 45 years old, patients with &gt;6 cycles and [Formula: see text] 5 inseminated oocytes. Results: Calcium supplementation increased both fertilisation (28.8% ICSI vs 49.7% ICSI-Ca, p&lt;0.0001) and clinical pregnancy rate (4.9% ICSI vs 25.0% ICSI-Ca: p&lt;0.05) in the low-fertilisation cohort but not in the normal-fertilisation cohort. Interestingly, utilisation rate increased in the normal-fertilisation cohort (32.6% ICSI vs ICSI-Ca: 44.9%, p&lt;0.01) but not in the low-fertilisation cohort, although the number of extra embryos utilised per patient after ICSI-Ca increased in both groups. Conclusion: Calcium supplementation appears not to be a detrimental addition to ICSI and may improve IVF outcomes, particularly for patients with a history of low fertilisation. Further investigations including prospective case matched studies or RCT are required to confirm these findings.

Abstract P094: Prevalence Of Polycystic Ovary Syndrome In Youth With Hypertension Disorders

Introduction: While Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders among adolescent females, it continues to be underdiagnosed and understudied. In particular, it is unknown whether youth with HTN may have a greater undiagnosed burden of PCOS compared to the general adolescent population. Patients with PCOS are at an increased risk for reproductive morbidities, hormone-dependent cancer, and metabolic and cardiovascular diseases. Furthermore, the relationships between metabolic syndrome (MBS) or obesity and PCOS in patients with HTN have not been fully investigated. Objectives: To estimate the prevalence of PCOS in adolescent females with HTN and investigate whether MBS and obesity increase this risk. Methods: This is an ongoing prospective cross-sectional study that has enrolled 12 of 40 participants to date. Inclusion criteria are females 10-18 years with HTN disorders of any cause and menarche for ≥2 years. Exclusion criteria are CAH, ovarian or pituitary cancer, Cushing syndrome, pregnancy, and a diagnosis of PCOS prior to HTN diagnosis. Data are collected via EHR abstraction and administered questionnaires, and include demographics, past medical, menstrual, and fertility histories, blood pressure, and physical characteristics including height, weight, and waist circumference. Our power and sample size calculations, made a priori, are based on estimating the difference in our population’s hypothesized PCOS prevalence (p1=0.25) with that of the general adolescent female population (p0=0.1) using the one-sample z-test of proportions. We will also use multivariable generalized linear models to estimate the risk of PCOS due to MBS or obesity. Results: The median systolic and diastolic blood pressures are 122.7 mmHg [113.8, 128.0] and 72.5 mmHg [68.8, 76.6]. The median waist circumference is 80.7 cm [76.5, 95.6]. The prevalence of PCOS is 17% (2/12), while 8% (1/12) have MBS and 58% (7/12) have obesity. Discussion: We are continuing to enroll new participants to reach our target enrollment of 40. Our results have the potential to educate clinicians to consider screening for PCOS in adolescent females who present with HTN to allow for prevention of the comorbidities associated with PCOS and to guide HTN treatment.

Long-Term Fertilization Strategy Impacts Rhizoctonia solani-Microbe Interactions in Soil and Rhizosphere and Defense Responses in Lettuce.

The long-term effects of agricultural management such as different fertilization strategies on soil microbiota and soil suppressiveness against plant pathogens are crucial. Therefore, the suppressiveness of soils differing in fertilization history was assessed using two Rhizoctonia solani isolates and their respective host plants (lettuce, sugar beet) in pot experiments. Further, the effects of fertilization history and the pathogen R. solani AG1-IB on the bulk soil, root-associated soil and rhizosphere microbiota of lettuce were analyzed based on amplicon sequencing of the 16S rRNA gene and ITS2 region. Organic fertilization history supported the spread of the soil-borne pathogens compared to long-term mineral fertilization. The fertilization strategy affected bacterial and fungal community composition in the root-associated soil and rhizosphere, respectively, but only the fungal community shifted in response to the inoculated pathogen. The potential plant-beneficial genus Talaromyces was enriched in the rhizosphere by organic fertilization and presence of the pathogen. Moreover, increased expression levels of defense-related genes in shoots of lettuce were observed in the soil with organic fertilization history, both in the absence and presence of the pathogen. This may reflect the enrichment of potential plant-beneficial microorganisms in the rhizosphere, but also pathogen infestation. However, enhanced defense responses resulted in retarded plant growth in the presence of R. solani (plant growth/defense tradeoff).

Understanding the impact of fertility history on health outcomes in later life.

ObjectivesAims of this research, involving data linkage and health outcomes, is to gain a full understanding of the impact of both fertility histories and childlessness on health outcomes mid-life accounting for socio-economic background and area of residence. The research draws on and extends work on reproductive histories and life-course outcomes.&#x0D; ApproachWe aim to extend this area of research, specifically for Scotland, using Census data (1991-2011) from the Scottish Longitudinal Study (SLS) linked to health data. The Census health measures – including the 2011 Census health condition question on mental health - are the research outcomes and the explanatory information is from Census socio-economic data (captured around peak fertility for the research cohort in 1991), along with the SMR02 Maternity and SMR04 Mental Health datasets. The time-frame for available data allows 20 year follow-up from the 1991 Census to mid-life for specific female SLS birth cohorts (born 1959-1966, aged ~45-52 in 2011).&#x0D; ResultsFrom preliminary modelling we initially find, for this specific female research cohort, high birth parity to be an important factor in relation to self-reported mental health conditions at follow-up in 2011, but not once socio-economic and area-level variables are controlled for.&#x0D; ConclusionPreliminary modelling also highlights that relationship status – single, married or cohabiting – to be important over that of legal marital status as recorded at Census. For limiting long-term illness as a health outcome the findings are similar.

Fertility experiences and later-life cognitive function among older adults in China.

The relationship between fertility history and human health has long fascinated scholars; however, whether there is a link between number of children and cognitive function in older adults remains unclear. We investigated the associations between parity and the timing of first and last births with the cognitive function of older adults over 65. The mini-mental state examination (MMSE) was selected as a tool to measure cognitive function. We analyzed data on 5847 older adults in rural and urban communities in China from the 2018 Chinese Longitudinal Healthy Longevity Survey using ordinary least squares. To further explore the transmission mechanism, we also conducted a mediating effect analysis. We found a negative association between number of children and cognitive function in older adults. Compared with older adults with four children, the MMSE scores of older adults with more than five children decreased significantly, and the score of older adults with zero to three children increased. Further, a late age at first birth (≥35) and a late age at last birth (≥35) were negatively associated with cognitive function. We also found that the associations between parity and cognition might be partly explained by variations in health. Our analyses provided evidence from China to support the link between fertility history and cognitive function that has been observed in previous international studies: We suggest that high parity (≥5) is negatively associated with cognitive function.

Characterization of primary female infertility in a Nigerian tertiary hospital: A case-control study.

Primary female infertility is a serious reproductive health concern amongst many women in Nigeria with associated psychosocial impact. There is a need for early prediction of this disorder for increased chances of fertility in Nigerian women. This study reported the anthropometric, sociodemographic, and clinical baseline characteristics of primary infertility females and studied their viability as predictors of primary infertility. This is a case-control study of primarily infertile (54) and fertile (50) Nigerian females aged 20-44 years recruited by random selection of patients who visited University College Hospital between August and November 2020. A clinical proforma was utilized to assess sociodemographic data, fertility history and clinical diagnosis of study participants. The body mass index (BMI) of both fertile and infertile females was in the overweight category (27.98±0.87 and 28.18±0.59, respectively). Both fertile and primary infertile females present a normal menarcheal age (13.68±0.27 and 13.91 ± 0.32 years, respectively), and there was no significant difference between the menarcheal age (p = 0.411) in both study groups. Ovarian disorder was the most contributing clinical diagnosis (67%) of primary infertility. There is a significant strong association between menarcheal age, ovarian factor infertility (χ2 = 13.839, φc = 0.458, p = 0.008) and tubal factor infertility (χ2 = 11.111; φc = 0.527, p=0.025). Females with primary infertility may present with overweight in no significantly different way than fertile females and BMI may not be useful in predicting primary infertility. However, menarcheal age may be a valuable tool to predict the ovarian and tubal factors in primary infertility.

Novel pathogenic splicing variants in helicase for meiosis 1 (HFM1) are associated with diminished ovarian reserve and poor pregnancy outcomes.

Diminished ovarian reserve (DOR) is associated with compromised fertility that affects approximately 10% of couples. Gene mutations are implicated in the pathogenesis of DOR. Here, we aimed to assess the clinical and genetic characteristics of two sisters with impaired fertility history. The two sisters showed DOR and suffered from recurrent pregnancy loss (RPL) in natural pregnancy and in vitro fertilization-embryo transfer (IVF-ET). Whole exome sequencing (WES) was performed for the proband and pathogenic variants detected were validated by Sanger sequencing in all available family members. Minigene assay was performed to evaluate the impact of sequence variants on splicing effect. Two novel heterozygous variants on the HFM1 gene, c.1978-2A > C and c.2680 + 3_2680 + 4delAT, were observed in the two patients. The genotype of their parents was all heterozygous, while the unaffected sister and brother did not carry the variants. Both variants could produce alternative transcripts compared to wild-type counterparts, which might result in protein dysfunction. Our results demonstrated that the pathogenic splicing variants in HFM1 are associated with DOR in these two sisters. Mutations in HFM1 may contribute to RPL and poor IVF-ET outcomes because of descending quality and quantity of oocytes. The study enriched the genetic defect spectrum of DOR and understanding of the roles of HFM1 in female reproduction.

Polarized adult fertility patterns following early parental death

Death of a parent during childhood has become rare in developed countries but remains an important life course event that may have consequences for family formation. This paper describes the link between parental death before age 18 and fertility outcomes in adulthood. Using the large national 2011 French Family Survey (INSEE–INED), we focus on the 1946–66 birth cohorts, for whom we observe entire fertility histories. The sample includes 11,854 respondents who have lost at least one parent before age 18. We find a strong polarization of fertility behaviours among orphaned males, more pronounced for those coming from a disadvantaged background. More often childless, particularly when parental death occurred in adolescence, some seem to retreat from parenthood. But orphaned men and women who do become parents seem to embrace family life, by beginning childbearing earlier and having more children, especially when the deceased parent is of the same sex.

The Role of Fertility and Partnership History in Later-life Cognition

AbstractCognitive ageing continues to be a significant burden for society and a primary contributor to individuals’ diminishing independence and quality of life. Therefore, improving our understanding of life-course influences on cognitive function is a necessity for public health. Parenthood and marriage are two such influences that may affect cognition in old age. Using the Health and Retirement Study, the relationship between family histories and cognitive functioning in adults in the ‘older’ age group in the United States is investigated through a sequence-analysis approach. The results show that most of the relationship between fertility and partnership history and cognition later in life is explained by childhood health and socioeconomic conditions, and current sociodemographic characteristics. However, those individuals who have never been married, and in particular those who have never been married and have had no children, report a significantly lower level of cognitive functioning in older age, especially women.

Fertility History and Risk of Cognitive Impairment Among Older Parents in the United States.

I work from a gendered life-course perspective to examine the association between older parents' fertility history (i.e., timing and parity) and their risk of cognitive impairment in the United States. I analyze nationally representative data from 9 waves over 16 years of the Health and Retirement Study (2000-2016). The sample includes 14,543 respondents (6,108 men and 8,435 women) aged 50 and older at the baseline survey. I examine the relationship between parity, age at first birth, and age at last birth with risk of cognitive impairment using nonlinear discrete-time hazard models. Adjusting for the effects of full covariates, there are U-shaped relationships between women's age at last birth and risk of cognitive impairment and between women's parity and risk of cognitive impairment. In the sensitivity tests, the relationships remain robust when sampling weights are applied, or mortality selection is corrected. Fertility timing and parity are likely factors associated with the risk of cognitive impairment for older women. Understanding fertility history and its impact on cognition can help identify the most vulnerable subpopulations, so that more effective interventions can be made to improve cognitive functioning among older adults.