CONCEPTION and PREGNANCY Females ovary eggs Males testes sperm Oogenesis female sex cell division Spermatogenesis male sex cell division Female = XX Male = XY

CONCEPTION and PREGNANCY FERTILIZATION During sexual intercourse (coitus) sperm enter female reproductive tract and live a day or two Eventually, one sperm penetrates and fertilizes the ovum

CONCEPTION and PREGNANCY Approximately 100 million sperm in 1 cc of semen Many sperm die before they reach the ovum 1. acidity of the vagina 2. higher temperature in the abd. of the women 3. lack of mobility

CONCEPTION and PREGNANCY INFERTILITY When conception does not occur – caused by damage to fallopian tubes, low sperm count, hormone imbalance, other disorders If sperm count is less than 20 million sperm per 1cc of semen, a man is considered sterile

CONCEPTION and PREGNANCY Zygote continues to divide as it travels down fallopian tube and is implanted in wall of uterus. At 7 days, the zygote becomes an embryo At 3 months, it becomes a fetus

CONCEPTION and PREGNANCY Implantation of Embryo Occurs about 6 days after ovulation and takes about a week to complete Coincides with Corpus Luteum stage and is completed about the time the Menstruation Stage is to begin First sign of pregnancy is a missed period

CONCEPTION and PREGNANCY Due to implantation, the uterine lining produces “HCG” THIS HORMONE IS ONLY PRODUCED IN PREGNANCY!! Function: causes corpus luteum to continue to produce progesterone

CONCEPTION and PREGNANCY HCG is detectable in blood about the time the period is due Not detectable in urine until approximately 2 weeks after a missed period

CONCEPTION and PREGNANCY Pregnancy prenatal period gestation Normal pregnancy = 40 weeks or 3 trimesters (3 months each) Quickening first recognizable movement of fetus, 4th-5th month Miscarriage spontaneous loss of the pregnancy

CONCEPTION and PREGNANCY