A nurse is preparing to administer penicillin G benzathine 1.2 million units IM now. The amount available is penicillin G benzathine 600,000 units/mL. How many mL should the nurse administer?
(Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)

Choice A Reason: Nagele's rule is a formula that estimates the due date by subtracting three months from the first day of the last menstrual period and adding seven days. However, this method assumes a regular 28-day cycle and may not be accurate for women with irregular cycles or who are unsure of their last menstrual period.

Choice B Reason: Ultrasound is the most accurate method of determining the estimated due date, especially in the first trimester. Ultrasound uses sound waves to create an image of the fetus and measure its size and development. Ultrasound can also detect any abnormalities or complications that may affect the pregnancy.

Choice C Reason: Gestation wheel is a circular calendar that estimates the due date by aligning the first day of the last menstrual period with a corresponding date on the wheel. However, this method also assumes a regular 28-day cycle and may not account for variations in ovulation or implantation.

Choice D Reason: Birth calculator is an online tool that estimates the due date based on various factors such as the last menstrual period, cycle length, ovulation date, conception date, or ultrasound date. However, this method may not be reliable as it depends on the accuracy of the input data and the algorithm used by the calculator.

Choice A Reason: This is correct because recurrent pelvic infections, such as pelvic inflammatory disease (PID), can cause scarring and inflammation of the fallopian tubes, which can impair the normal movement of the fertilized egg to the uterus. This can increase the risk of ectopic pregnancy, which is a life-threatening condition where the fertilized egg implants outside the uterine cavity, usually in the fallopian tube.

Choice B Reason: This is incorrect because ovarian cysts are fluid-filled sacs that develop in or on the ovaries. They are usually benign and do not affect fertility or pregnancy. However, some types of ovarian cysts, such as endometriomas or dermoid cysts, may require surgery to remove them, which can cause damage to the ovaries or fallopian tubes and increase the risk of ectopic pregnancy.

Choice C Reason: This is incorrect because use of oral contraceptives for 8 years is not a risk factor for ectopic pregnancy. In fact, oral contraceptives can reduce the risk of ectopic pregnancy by preventing ovulation and fertilization. However, if a woman becomes pregnant while taking oral contraceptives, she should stop taking them and consult her doctor, as they may have adverse effects on the developing fetus.

Choice D Reason: This is incorrect because heavy, irregular periods are not a risk factor for ectopic pregnancy. They may indicate other conditions such as hormonal imbalance, uterine fibroids, polycystic ovary syndrome (PCOS), or endometriosis, which can affect fertility or pregnancy, but not necessarily cause ectopic pregnancy.