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0ASSISTED REPRODUCTIVE TECHNOLOGIES FOR WOMEN WITH REPRODUCTIVE DYSFUNCTION Soliyeva R.B.
Soliyeva Ranokhon Bokhodirjon kizi - PhD, Assistant, DEPARTMENT OF OBSTETRICS AND GYNECOLOGY, ANDIJAN STATE MEDICAL INSTITUTE, ANDIJAN, REPUBLIC OF UZBEKISTAN
Abstract: assisted reproductive technology (ART) includes fertility treatment in which either eggs or embryos are handled outside a female's body to promote successful pregnancies and healthy offspring. Current ART procedures encompass in vitro fertilization with or without intracytoplasmic sperm injection.
Keywords: ovarian stimulation, oocyte retrieval, fertilization, embryo culture, and embryo transfer, genetic testing.
The most common complication of ART is related to the consequences of multiple pregnancy, which can be prevented or minimized by reducing the number of embryos transferred to the uterus, commonly single embryo transfer. ART has been shown to be variably associated with adverse short- and long- term perinatal outcomes, including cerebral palsy, autism, neurodevelopmental imprinting disorders, and cancer. However, there is uncertainty as to whether reported problems are related to the ART procedure itself, to factors related to infertility, to other medical and environmental factors, or a combination thereof. From a pathophysiological perspective, whether ART alters epigenetic mechanisms of gene expression, leading to later developmental, medical, and behavioral disorders, is an area of active investigation. With the meticulously conducted short- and long- term outcome studies completed so far, overall, and after controlling for multiple gestations and preterm delivery, the results suggest that ART is a safe procedure, offering hope to many parent(s) wishing for a healthy child. This paper highlights ART methods and the risk factors and confounders in the interpretation of short- and long- term outcome data, providing the reader with a means to evaluate findings and conclusions of outcome studies. The crucial components of the female anatomy in understanding ART are the ovaries, fallopian tubes, and uterus. The ovaries are the third component of the hypothalamic-pituitary-ovarian axis (HPO), which is a complex feedback loop that controls the female menstrual cycle. The ovaries are the female gonads, paired oval-shaped structures that embryologically derive from the mesonephric ridge before descending in the pelvis. The ovaries are where oocytes mature and develop. Production of estradiol and progesterone also derive from the ovary. The ovaries have two peritoneal attachments - the ovarian ligament and the suspensory ligament of the ovary. The ovarian ligament attaches the ovary to the uterus. The suspensory ligament of the ovary attaches the ovary to the pelvic sidewall and contains the neurovascular supply to the ovary. Understanding this anatomy is important in understanding the transvaginal approach to oocyte retrieval.
The uterus responds to the fluctuating hormones produced by the HPO axis. It lies in the pelvis, between the bladder and rectum. It consists of the corpus (the body of the uterus) and the cervix, which connects the uterus to the vagina. The uterine body consists of three layers - the perimetrium, myometrium, and endometrium. The endometrium is composed of two layers, the functionality, and the basalis. The functionalis layer undergoes cyclical hormonal changes to prepare for implantation with each menstrual cycle. Increasing estrogen levels during the follicular phase of the menstrual cycle results in endometrial glandular proliferation. During the luteal phase, progesterone levels rise, causing the endometrium to undergo secretory changes. If an embryo does not implant during the cycle, estrogen and progesterone levels fall, resulting in degradation of the functionalism layer, which then sloughs off with menses. [2]
The fallopian tubes are muscular tubes that extend on both sides laterally from the uterus towards the ovaries. They aid in the transfer of the ovum to the uterus, often with fertilization happening within the tube itself. The tubes aid in this transfer by sweeping up the ovum at their fimbriated ends, with smooth muscle contractions and ciliated columnar epithelial cells transferring the ovum or embryo to the uterus where it can implant if fertilized. Before initiation of ART, maternal risks of the ART techniques and pregnancy itself are discussed with the patient. Certain maternal conditions, particularly cardiopulmonary conditions such as pulmonary hypertension and heart failure, are relatively contraindicated conditions for pregnancy. Pre-conception counseling and evaluation to screen for such conditions should be conducted. Even in such patients, gestational carrier options can be utilized. The vitro fertilization is the most commonly utilized assisted reproductive technology. It involves the collection of oocytes from the ovary, followed by fertilization in vitro, and is completed with transferring the resulting embryo into a uterus. It involves various steps outlined below, including controlled ovarian stimulation, oocyte retrieval, fertilization, embryo culture, and embryo transfer. Additionally, preimplantation genetic testing and intracytoplasmic sperm injection may also be included in the process. Cryopreservation with vitrification is then used to freeze excess embryos or for fertility preservation of eggs or embryos. The most common complication of ART is the risk of multifetal pregnancies. In 2009, 41.1% of infants conceived via ART were of multifetal pregnancies (compared to 3.5% of infants in the general population). The effort to reduce multifetal gestation via reducing the number of embryos transferred at once has resulted in a significant reduction—by 2017, 73.6% of ART-conceived infants were from singleton pregnancies.
Multifetal gestation pregnancies have both maternal and fetal consequences. Pregnancies have a higher likelihood of being complicated by various antenatal conditions, including hyperemesis gravidarum, gestational diabetes, and hypertensive diseases of pregnancy. Multifetal gestation pregnancies also have worse fetal and neonatal outcomes
than singleton pregnancies, with a significant increase in preterm birth and the associated increase in the risk of stillbirth (fivefold) and neonatal death (sevenfold).
IVF providers limit multifetal gestation pregnancies through several avenues, including low-dose stimulation regimens, close hormone and follicle monitoring during stimulated cycles, and limiting the number of embryos transferred per cycle. Once a multifetal gestation is diagnosed, appropriate counseling regarding the increased risks in pregnancy should be discussed with the patient, and the option of multifetal reduction, when appropriate, should be offered.
Beyond multifetal gestation, singleton IVF pregnancies are also possibly associated with various increased risks compared to naturally conceived pregnancies. These risks include perinatal mortality, preterm delivery, low birth weight, cesarean section, placenta previa, placental abruption, and preeclampsia. These possible risks should also be discussed when counseling patients, but with caution, as the quality of data is limited by the existing study designs. Standardized tracking of outcomes of ART pregnancies to include these outcomes would improve the quality of evidence for or against these potential risks of IVF-conceived pregnancies. There is also limited evidence of a low-level increased risk of birth defects in patients undergoing IVF, particularly with ICSI, though again quality of evidence is low. It is reasonable to offer ultrasonographic surveillance during IVF-conceived pregnancies, such as with fetal echocardiography.
References
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3. Van Eekelen R., van Geloven N., van Wely M., Bhattacharya S., van der Veen F., Eijkemans M.J., McLernon D.J. IVF for unexplained subfertility; whom should we treat? Hum Reprod. 2019 Jul 08;34(7):1249-1259.
4. Noyes N., Labella P.A., Grifo J., Knopman J.M. Oocyte cryopreservation: a feasible fertility preservation option for reproductive age cancer survivors. J Assist Reprod Genet. 2010 Aug;27(8):495-9.
5. Practice Committee of the American Society for Reproductive Medicine and Practice Committee of the Society for Assisted Reproductive Technology. Electronic address: [email protected]; Practice Committee of the American Society for Reproductive Medicine and Practice Committee of the Society for Assisted Reproductive Technology. Recommendations for practices utilizing gestational carriers: a committee opinion. Fertil Steril. 2017.
