In-vitro fertilization has often been the mainstay solution for dealing with infertility, however it has also been cited as being responsible for an unusual side effect: multiple pregnancies. Twins, triplets, and even higher order multiples have been reported in women who have no family history of multiple births. Although the prospect of twins and triplets is often thought of as an appealing scenario for many couples facing infertility, the medical issues and consequences affecting both mother and infant cannot be ignored.
Multiple pregnancies are more likely to result in difficult consequences, such as low birth weight as well as preterm birth. Preterm birth is the birth of a baby at a gestation age less than 37 weeks. Its associated diseases include a wide spectrum of health issues, ranging from neurological problems and respiratory problems to congenital heart defects and infection. Not surprisingly, infant mortality for these cases is high.
According to several studies, without the intervention of in-vitro fertilization, the chance of a pregnant woman to have natural fraternal twins is about 1 in 60, and the prospect of having identical twins is far less: about 1 in 250. Fertility drugs used in IVF have increased these chances dramatically such that the chance that a woman would have multiple births under IVF is tenfold greater. This is primarily due to the number of embryos transferred in one IVF cycle. Reproductive medicine has focused efforts on lowering the risk of multiple births in IVF while trying to maintain success rates. By limiting the number of embryos transferred in an IVF cycle, the risk of multiple pregnancies can be mitigated.
Women and couples with infertility can follow these guidelines to reduce their risk of multiple pregnancies:
- Seek help as soon as possible. If you have been unsuccessfully trying to conceive or you know that there is a problem, it is important to seek immediate help from a fertility specialist. The risk of multiple births in IVF is correlated with the woman’s maternal age. Younger women are more likely to get pregnant with fewer embryos, and the risk of having multiples is lower.
- Single embryo transfer is recommended. Women under the age of 35 and undergoing a fresh IVF cycle should be offered a single embryo transfer. The success rates of single-embryo transfers are comparable with multiple-embryo transfers. If fertility specialists advise the transferring of more embryos, it is important to get an explanation to justify the higher number of embryos. A single blastocyst transfer may also be done, as long as the candidate is not over 35 years of age.
- CGH Screening helps select the best embryos. Comparative Genomic hybridization (CGH) is a newly developed screening technique that aims to identify the healthiest embryo to transfer in an IVF cycle. CGH involves a biopsy from the outer cell layer during the more mature blastocyst stage on Day 5 without any damage to the embryo. Eventually, CGH may improve IVF success in the Philippines to a much greater proportion.