A nurse in a clinic is teaching the mother of a 4-month-old infant who has been breastfed. The mother plans to switch her infant to an iron-fortified formula. Which of the following should be included in the teaching?

Choice A reason:
Urinary frequency typically begins early in pregnancy due to hormonal changes and increased blood volume leading to more fluid being processed by the kidneys and ending up in the bladder. While it often improves in the second trimester as the uterus rises into the abdominal cavity, poor bladder tone is not typically cited as a reason for its continuation.

Choice B reason:
While urinary frequency can be seen as a minor inconvenience, it should not be ignored. It is a normal physiological change during pregnancy. However, if it is accompanied by pain, burning, or any other symptoms, it could indicate a urinary tract infection, which requires medical attention.

Choice C reason:
There is some predictability to urinary frequency in pregnancy. It often starts in the first trimester, improves in the second, and may return in the third trimester as the growing baby and uterus exert pressure on the bladder.

Choice D reason:
This choice is accurate. Urinary frequency is common in the first trimester due to hormonal changes and the growing uterus pressing on the bladder. It often returns in the third trimester when the baby "drops" and the head presses on the bladder. This is a normal part of pregnancy and usually does not indicate any complications.

Choice A reason: The rubella vaccine is a live attenuated virus vaccine, which is generally not recommended during pregnancy due to the theoretical risk to the fetus. However, it is safe to receive the rubella vaccine while breastfeeding; it does not pose a risk to the nursing infant.

Choice B reason: The varicella vaccine, which is also a live virus vaccine, should not be administered during pregnancy because of the potential risk to the fetus. Women should be vaccinated before pregnancy or in the postpartum period.

Choice C reason: The Tdap vaccine, which protects against tetanus, diphtheria, and pertussis (whooping cough), is recommended for all pregnant women during each pregnancy, regardless of their previous history of receiving the vaccine. The optimal timing for Tdap administration is between 27 and 36 weeks of gestation to maximize the transfer of antibodies to the baby.

Choice D reason: Pregnant women are encouraged to receive the inactivated influenza vaccine at any point during their pregnancy. The flu shot is safe during pregnancy and helps protect both the mother and the baby from the flu and its complications.