Significant Difference In Pregnancy Rate Research Articles

Multinational comparative clinical trial of long-acting injectable contraceptives: norethisterone enanthate given in two dosage regimens and depot-medroxyprogesterone acetate. A preliminary report

A multicentre phase III clinical trial has been undertaken to compare norethisterone enantate (NET-EN) given by two different treatment regimens and depot-medroxyprogesterone acetate (DMPA). After 18 months of observation, preliminary findings are reported for 1,589 women who received DMPA 150mg every 90 days; 790 women who received NET-EN 200mg every 60 days; and 796 women who received NET-EN, 200mg every 60 days for 6 months, then 200mg every 84 days.The overall discontinuation rates per 100 women were similar for all three treatment groups over the 18 months observation (61.8–63.5 per 100 women). The discontinuation rates for bleeding problems and for personal reasons were also similar for all three treatment groups. However, terminations due to amenorrhoea were significantly higher among DMPA users (12.1 and 17.4 per 100 women at 12 and 18 months) as compared with both NET-EN groups (6.8–8.2 per 100 women at 12 months and 10.4–10.9 per 100 women at 18 months).The only significant difference in pregnancy rates observed between the three groups was a higher rate at 18 months among NET-EN (84 days) users (1.6 per 100 women), as compared with DMPA users (0.2 per 100 women). There was no overall significant difference between the two NET-EN groups, although between the 6 and 18 month's follow-up when the two NET-EN regimens diverged, the NET-EN (84 days) users' pregnancy rate rose significantly, wherease in the NET-EN (60 days) group the pregnancy rate did not change. There was a significantly higher weight gain in those subjects using NET-EN at 60-day intervals compared with those using it at 84-day intervals.

Microsurgical Reversal of Female Sterilization: The Role of Tubal Length

A group of 25 women who had undergone tubal sterilization by a variety of techniques underwent microsurgical reanastomosis. The length of tube remaining and the segments of tube involved were carefully noted preoperatively, but were not used as a basis for selection of patients. The only criterion utilized for selecting patients was the presence of fimbriae on at least one side. In all patients, anatomical patency was achieved at surgery. Normal intrauterine pregnancy was directly related to tubal length. Of seven patients who had less than 3 cm of tube, none achieved pregnancy. Of seven patients who had 3 to 4 cm of tube, three achieved a normal intrauterine pregnancy. Among 11 patients who had over 4 cm of tube, all 11 achieved a normal intrauterine pregnancy. No significant difference in pregnancy rate was noted in women who had short segmants of ampulla so long as total tubal length was adequate.

Non-surgical transfer of bovine eggs: investigation of some factors affecting embryo survival

In an investigation on the effect of position of deposition of the egg within the uterus, surgical transfer of single eggs to the tip of the horn resulted in a significantly higher pregnancy rate than transfer to the base. To determine embryo survival at differing times after transfer single eggs were transferred non-surgically to the base of the uterine horn. The highest pregnancy rate occurred in a group of heifers slaughtered 16 to 17 days after oestrus followed by heifers slaughtered on days 24 to 26. The lowest pregnancy rate occurred in a group where pregnancy diagnosis was on day 42 by rectal palpation. The pregnancy rates of the highest and the lowest groups were significantly different. The pregnancy rate was increased in a group of heifers which were treated with human chorionic gonadotrophin from day 13 to 24 and palpated per rectum on day 42 to determine pregnancy. The presence or absence of penicillin and streptomycin in the medium and of passing differing volumes into the uterus after non-surgical transfer of single eggs using a glass pipette had no effect on pregnancy rate and there was no significant difference in pregnancy rate and there was no significant difference in pregnancy rate between the groups using different volumes of transfer media. The position of the egg within the uterine lumen after transfer contributes to the reduced pregnancy rate achieved after nonsurgical transfer when compared with the surgical method. The greatest proportion of embryonic death after non-surgical transfer occurs after day 17 and there is some evidence that human chorionic gonadotrophin treatment can improve embryo survival. The use of comparatively small volumes of medium to eject the egg into the uterus may be preferable to achieve maximum pregnancy rates.

Induced or synchronized puberty in heifers.

Three experiments were conducted to examine different hormone treatments for their effectiveness in inducing or synchronizing a fertile estrus in prepuberal heifers. In experiments I and II, heifers which averaged 8.5 months of age and 249 kg in weight were given treatment E (5 mg E2β, experiment I), treatment PE (silastic rubber implant containing 2.1 g progesterone for 6 days and an injection of 5 mg E2β 24 hr after implant removal, experiments I and II) or treatment S-6 (6 mg SC-21009 progestogen implant for 6 days with an injection of 3 mg SC-21009 and 5 mg estradiol valerate at the time of implanting, experiment II). In experiment I, treatment PE increased the number of heifers showing estrus within 4 days (P<.01) and ovulating (P<.05). However, no significant differences in pregnancy rate were found after 4 or 45 days of breeding. In experiment II, more PE treated heifers than S-6 treated heifers were in estrus after 4 days (P<.01) but pregnancy rates were low and differences were small after 4 (P>.25) or 45 (P<12) days of breeding. In experiment III, heifers which averaged 13.7 months of age and 323 kg in weight were divided into puberal and prepuberal. The prepuberal heifers were given treatment S-9 (same as S-6 except implant period was 9 days) or SE (SC-21009 implant for 9 days with an injection of 5 mg E2β 24 hr after implant removal). Detection rate of the first estrus (after 4 days in prepuberal vs 22 days in puberal) was similar (P>.5) in all groups. Pregnancy rates were lower in SE heifers at the first estrus (P<.01) and after 45 days of breeding (P<.05). These data indicate that a fertile estrus can be hormonally induced or synchronized in prepuberal heifers of normal age (13 to 15 months) and to a lesser degree in very young heifers (<9 months).

Experience with the copper T and silicone shell loop in parous women: A randomized study

A randomized study was conducted to compare the performance of two IUDs, the Copper T-200 and the Silicone Shell Loop D, in parous women. The number of insertions for the TCu 200 and SCS-D were 267 and 221, respectively. The results were analyzed at the end of one and two years, utilizing for the first time in a contraceptive study, the log-rank method of life-table analysis. The findings showed no significant difference in pregnancy rates. The TCu 200 had a significantly higher expulsion rate and the SCS-D had a significantly higher rate of removal for bleeding and pain at the end of two years.

A Comparison of Two Large-Scale Studies of the Use-Effectiveness of IUDs

The results of the California Cooperative Statistical Program for Evaluation of Intrauterine Devices (known as FPS for Family Planning Study) and the Cooperative Statistical Program for Evaluation of Intrauterine Devices (CSP) are compared with respect to such elements as demographic characteristics of acceptors continuation rates percents lost to follow-up and annual and cumulative rates of events by type of termination over a 2-year period. In general initial acceptors of loop D in the FPS were younger and of higher parity at first insertion than those in the CSP. 1/2 of the FPS acceptors of loop D were inserted within 3 months of last pregnancy termination compared with less than 1/3 of the CSP acceptors. Continuation rates are lower in the FPS than in the CSP. This may be partially due to a difference in assumptions and procedures. There are no significant differences in pregnancy rates between the 2 studies nor in first expulsion rates except for all segment where the FPS rates are significantly lower. Removals for pain or bleeding show significant differences between the 2 studies for first year first segment annual and 2-year cumulative termination rates. In the category removals other medical the various rates are consistently significantly higher for the FPS than for the CSP in the absence of controls. For removals planned pregnancy there are significantly higher FPS rates for uncontrolled cases and for removals other personal there are lower FPS 2-year cumulative competing risk rates for both first segment and all-segment terminations and for all-segment closures. Age and parity could account for the differences in these uncontrolled cases. All things considered the FPS findings would appear to justify reinforced confidence in the CSP findings. Differences in assumptions definitions and procedures may be responsible for some variations in results. Where age and parity controls have been employed significant differences are rare.