Human Reproductive Anatomy Quiz

Hormones and Reproductive Functions

• Progesterone increases throughout pregnancy, relaxing the uterus and maintaining the pregnancy.
• Estrogen is responsible for muscle hypertrophy in the uterus and contributes to the thickening of the endometrium.
• Oxytocin from the posterior pituitary gland (PPG) plays a role in uterine contractions during labor and ejection of milk postpartum.
• During birth, the cervix has no ruggae, allowing easier passage for the baby.

Anatomy and Physiology of the Uterus

• Uterus is composed of three layers: perimetrium, myometrium, and endometrium.
• Myometrium muscles have a unique “figure of 8” arrangement, enhancing uterine contractions.
• The upper segment (fundus) is most active during pregnancy and is the primary site for placenta implantation.
• Placenta previa is a condition where the placenta obstructs the birth canal, leading to painless bleeding.

Lochia and Menstruation

• Lochia refers to the vaginal discharge following childbirth, with three stages: rubra, serosa, and alba, each with distinct durations and characteristics.
• Menstrual flow differs from lochial discharge; menstrual blood never clots and typically ranges from 30 to 80 ml, lasting 2-6 days.

Labor and Contractions

• Braxton Hicks contractions prepare the body for labor and become more significant in the later months of pregnancy.
• The reduction of progesterone levels triggers the release of oxytocin, contributing to labor onset.
• The physiologic retraction ring separates the upper and lower uterine segments during contractions.

Breastfeeding and Hormonal Impacts

• Breastfeeding serves not only as nutrition but also as a natural method of birth control, suppressing ovulation for up to 6 months.
• Prolactin is stimulated when the baby suckles, promoting milk production.
• Estradiol and estriol are key estrogen forms produced by the ovaries and placenta, respectively.

Fallopian Tube and Fertilization

• The fallopian tube facilitates the passage of a fertilized egg; healthy tubes are essential for fertilization.
• The ampulla is the site of fertilization and is targeted during procedures like tubal ligation.
• Pelvic inflammatory disease and surgical interventions can lead to ectopic pregnancies.

Ovary and Menstrual Cycle

• At birth, females have approximately 300,000-400,000 primordial ova; this number decreases significantly over time.
• Menarche typically occurs between ages 9-17, marking the start of the reproductive phase.
• The menstrual cycle begins with hormonal changes that prepare the endometrium for potential implantation.

Male Reproductive Anatomy

• The scrotum protects testes, maintaining optimal temperature for sperm production.
• Sperm production occurs in the testes; the epididymis stores mature sperm.
• Seminal fluid from the prostate gland and seminal vesicles provides nourishment and a supportive environment for sperm.

Birth Control Methods

• Coitus interruptus and withdrawal are behavioral birth control methods, though they carry risks.
• Natural family planning relies on understanding ovulation timing, as the ovum is fertilizable for only 18-24 hours.
• Chemical contraceptives like nonoxynol-9 act to kill spermatozoa and prevent fertilization.

Pregnancy and Menopause

• The body undergoes significant hormonal changes during pregnancy, with increased progesterone and estrogen levels facilitating fetal development.

• Menopause marks the cessation of menstruation, often accompanied by symptoms due to hormone fluctuation.### Contraceptive Methods Overview

• Chemical Contraceptives

  • Usage of spermicides can alter the vaginal pH, making it more acidic.
  • Common side effect of spermicides is vaginitis.

• Implantable Contraceptives

  • Norplant is a synthetic progestin implantable method placed in the upper arm.
  • Effective for 5 years, containing 6 progestin capsules.
  • Not readily reversible, and should be felt but not visibly seen.
  • Cost-effective, administered every 3 months, with absorption increased by minimal movement at the site.

Intrauterine Device (IUD)

• A small, flexible device inserted into the uterine cavity, typically when the woman is menstruating.
• Ensures the cervix is open, confirming the absence of pregnancy.
• Disrupts the normal uterine environment, leading to an abnormal lining.
• Inhibits implantation through:
  • Local inflammatory response.
  • Prostaglandin production.
  • Interference with enzymatic and hormonal activities.
  • Increased motility of the ovum in the fallopian tube.
• Also immobilizes sperm during passage through the uterus.
• Highly effective with 98-99% efficacy during the first two years, decreasing by 1% each subsequent year.

Oral Contraceptive Pills (OCPs)

• Available in 21 and 28-day preparations, with a 7-day placebo period (iron supplements).
• Must adhere to prescribed schedules, starting the first day of menstruation for the 28-day prep or by the 5th day for the 21-day prep.
• Recommended to take pills with food to minimize gastric irritation.
• Consistency in timing enhances effectiveness; if missed, take as soon as remembered.
• Notable interactions with certain health conditions:
  • Contraindicative in cases of undiagnosed vaginal bleeding, thromboembolic disorders, pregnancy (teratogenic effects), liver disease, coronary artery, cerebrovascular disease, heavy smoking, and breastfeeding (can suppress estrogen).

Post-Insertion Care

• After IUD insertion, patients should check the string weekly for the first month and monthly thereafter.
• Immediate medical attention is warranted if the string is not felt, indicating possible complications.