RNSG 1412 (Ob/Pedi) - Exam 4, PPT & Learning Guide: Conception & Fetal Development & Prenatal Diagnostic Tests|Female Reproductive Cycle, Ovarian Follicular Development, Ovulation, Luteal Phase, Endometrial Proliferation, Secretory & Menstrual Phases, Hor

RNSG 1412 (Ob/Pedi) - Exam 4, PPT & Learning Guide: Conception & Fetal Development & Prenatal Diagnostic Tests|Female Reproductive Cycle, Ovarian Follicular Development, Ovulation, Luteal Phase, Endometrial Proliferation, Secretory & Menstrual Phases, Hormonal Regulation (FSH, LH, Estrogen, Progesterone, hCG), Fertilization, Gametogenesis, Zygote Formation, Embryonic Development, Organogenesis, Fetal Period, Placental Function, Chorion & Amnion, Amniotic Fluid, Umbilical Cord, Teratogens, Monozygotic & Dizygotic Twins, Prenatal Diagnostic Ultrasound, Doppler Flow Assessment, Alpha-Fetoprotein Screening, Chorionic Villus Sampling, Amniocentesis, Percutaneous Umbilical Blood Sampling, Non-Stress Test, Contraction Stress Test, Biophysical Profile, Maternal Kick Counts, Myometrial Fiber Function, Pelvic Anatomy Exam Questions Verified and Provided with Complete A+ Graded Rationales Latest Updated 2026 Female Reproductive Cycle (aka menstrual cycle) consists of: Ovarian Cycle Endometrial Cycle The 28 day Ovarian Cycle Follicular Phase: Starts with first day of menses Lasts about 14 days Ovulatory Phase: 2 days Luteal Phase: Corpus Luteum persists for about 12 days Ovarian cycle (Follicular Phase) AP FSH and LH Several graafian follicles start growing One matures and starts secreting estrogen Depresses FSH secretion and maturation of other follicles Responsible for proliferative phase of endometrial cycle Ovarian cycle (Ovulatory Phase) Mid Ovarian cycle Increase in LH, FSH, and progesterone Slight decrease in estrogen A single follicle releases its mature ovum OVULATION Clear, thin mucus with elasticity (spinnbarkeit) aids in promoting passage for sperm One ovum per month is discharged from the ovary. It is transported into the fallopian tube where it begins its journey through the tube in search for the sperm. Ovarian Cycle (Luteal Phase) The follicle’s remaining cells in the ovary become a “corpus luteum” and secretes estrogen and progesterone for +/- 12 days The endometrium thickens so that it can receive a fertilized ovum (secretory phase of the endometrial cycle) Endometrial Cycle Controlled by the hormones produced during the "Ovarian Cycle" •Proliferatory Phase •Secretory Phase •Menstrual Phase If conception occurs? The female reproductive cycle is interrupted when conception occurs. NOW... The conceptus secretes human chorionic gonadotropin (hCG) (effect of hCG) Corpus Luteum persists and continues to secrete estrogen and progesterone until the placenta assumes this function (luteo-placental shift) This illustrates the effect of human Chorionic Gonadotrophin (hCG) on the corpus luteum. The fertilized egg secretes hCG. This stimulates the corpus luteum to produce more progesterone and grow bigger. Normally, in the absence of hCG, the corpus luteum will regress, stop functioning after +/- 12 days, and menstruation will begin. Hormonal Cycle •FSH- Follicle Stimulating Hormone -FSH stimulates the growth and development of immature ovarian follicles •LH - Luteinizing Hormone -Assists with maturation of follicles. LH surge triggers ovulation as well as the development of the corpus luteum •ESTROGEN -responsible for proliferation of endometrium •PROGESTERONE -Pro-gestation. Maintain hospitable environment of endometrium in anticipation of fertilized ovum. The male contribution 1.Seminal fluid outside cervix 2.Sperm reach ovum in fallopian tube 3.Capacitation on the way 4.One spermatozoon penetrates corona radiata and zona pellucida of ovum 5.Nuclei of sperm and ovum merge 6.Changes in zona pellucida limit fertilization to one sperm only Fertilization The chromosomes from the sperm and ovum merge. Fertilized egg: Total of 46 chromosomes Sex of baby determined at this time by sperm: X =female, Y = male Maintaining the pregnancy Implantation occurs 6-10 days after conception The conceptus needs estrogen and progesterone to keep the decidua in the secretory phase. How does it do this? By secreting human chorionic gonadotropin (hCG) the conceptus signals the corpus luteum... In response to the hCG the corpus luteum persists... and continues to secrete estrogen and progesterone to maintain the decidua in the secretory phase. Implantation •The site of implantation is important.Upper uterus (fundus) is best. -Thick uterine lining prevents the placenta from attaching too deeply -Thick uterine muscles can more effectively compress open vessels after placenta detaches (stage ?) and thereby limiting blood loss. Tiny chorionic villi from the conceptus bury into the decidua. Together t