Short answer: It s necessary, if she has an infertility problem & you re planning to have a baby. Detailed answer: Thank you for asking on HealthcareMagic.com, providing better healthcare for you. HuCoG or Human chorionic gonadotropin (HCG) is a hormone that supports the normal development of an egg in a woman s ovary, and stimulates the release of the egg during ovulation. HCG is used to cause ovulation and to treat infertility in women. Some women using this medicine have developed a condition called ovarian hyperstimulation syndrome (OHSS), especially after the first treatment cycle. It can be a life-threatening condition, so please see a doctor right away if she has any of the following symptoms of OHSS: severe pelvic pain, stomach pain and swelling, shortness of breath, weight gain, diarrhea etc. Hope this answers your question. If you have additional questions or follow up questions then please do not hesitate in writing to us. I will be happy to answer your questions. Wishing you good health.Please don t forget to give your valuable feedback and five star rating, to help me assist you in a better way. Click at I Find This Answer Helpful too . Please, write a review about your experience with me.