Why is my menstrual period delayed by more than ten days if I'm not pregnant?

Generally, if menstruation is delayed for more than ten days without pregnancy, possible causes may include prolonged mental anxiety, excessive dieting for weight loss, polycystic ovary syndrome (PCOS), hyperprolactinemia, thin endometrium, and other related factors. It is recommended to seek timely medical consultation to identify the specific cause and receive appropriate treatment under a physician's guidance. Detailed explanations are as follows:

1. Prolonged Mental Anxiety: Long-term tension or anxiety can affect the hypothalamic-pituitary-ovarian axis, leading to hormonal imbalances and delayed menstruation. It is important to adjust one's mindset by listening to music, exercising, and ensuring 7–8 hours of sleep daily, avoiding late nights to help restore normal hormone levels.

2. Excessive Dieting for Weight Loss: Overly restrictive eating leading to rapid weight loss can suppress estrogen synthesis and disrupt the menstrual cycle. It is essential to resume a balanced diet with adequate protein and vitamin intake—for example, consuming eggs, milk, and vegetables daily—to gradually restore a healthy weight and avoid blind dieting.

3. Polycystic Ovary Syndrome (PCOS): Hormonal imbalances cause abnormal ovulation, often manifesting as delayed menstruation and hirsutism. Patients should follow medical advice to use medications such as ethinylestradiol cyproterone tablets, drospirenone ethinylestradiol tablets, or desogestrel ethinylestradiol tablets to regulate hormone levels.

4. Hyperprolactinemia: Elevated prolactin levels can suppress ovulation, causing delayed menstruation or even amenorrhea, sometimes accompanied by breast galactorrhea. Patients should follow medical instructions to take medications such as bromocriptine mesylate tablets, vitamin B6 tablets, or cabergoline tablets to lower prolactin levels.

5. Thin Endometrium: Repeated uterine cavity procedures or insufficient estrogen may result in inadequate endometrial thickness, affecting the onset of menstruation. Mild cases can follow medical advice to use medications such as estradiol valerate tablets, conjugated estrogens tablets, or nylestriol tablets to promote endometrial growth.

In daily life, maintain a regular sleep schedule and avoid excessive fatigue. In terms of diet, avoid spicy and cold foods, and consume more phytoestrogen-rich foods such as soy products. Engage in moderate exercise like brisk walking or yoga to help regulate the endocrine system and maintain a stable menstrual cycle.