NEONATAL FOLLOW-UP OF BABY BORN DERIVED FROM A TWO PRONUCLEI PLUS ONE MICRO PN OOCYTE FOLLOWING INTRACYTOPLASMIC SPERM INJECTION

Abstract

A micro PN is very small and can be overlooked when observed under a microscope. Furthermore, it is difficult to see when it overlaps with the normal nucleus. Out of 5,026 oocytes derived by intracytoplasmic sperm injection, 0.7% showed micro PN. After performing chromosome and ploidy analysis on embryos that have grown to blastocysts, micro PN-derived balanced-diploid blastocysts have been transferred into three patients and childbirth has been reported in two patients. (Capalbo et al, Fertility and Sterility, 2017) However, there are no reported cases of developmental follow-up of babies born from micro PN oocytes. Therefore, we report on the neonatal follow-up of baby born derived from a two pronuclei plus one micro PN oocyte. Patient seeking infertility treatment in a well-established private IVF clinic. The birth weight and the height and weight at one and a half and three years old of one case in which a micro-PN-derived blastocyst was transferred were compared with the results of the 2010 Infant Physical Growth Survey by the Ministry of Health, Labor and Welfare (MHLW) of Japan. The patient was a nulliparous woman and treatment started at the age of 31. Therapy started in August 2009, and AIH was performed 6 times in total upto February 2011, but pregnancy was unsuccessful. After that, 19 oocytes were collected by controlled ovarian stimulation in April 2014. As a result of insemination of the collected oocytes, microPN (size: 9 μm) appeared in one of the ICSI-derived embryos, which was about one-third the size of the male and female pronuclei. Afterwards singleton vitrified-warmed embryo transfer in hormone replacement cycle was performed twice by July 2014. As a result of transferring micro PN-derived blastocyst (Gardner’s score 3AB) at the time of the second embryo transfer, a girl was born by Caesarean section at 38 weeks, and the weight was 3.02 kg, which was within the normal range of the growth curve of data from children in MHLW database. The height at one and a half years was 74.8 cm and the weight was 9.45 kg, which was within the normal range of the growth curve of the children by MHLW. At the age of three, she was 87 cm tall and weighed 13 kg. The height was slightly below the growth curve, but there were no other abnormalities in the child. Follow up from birth to age 3 years did not report any abnormalities or severe growth retardation in the infant.