https://www.wisdomlib.org/hinduism/book/chandogya-upanishad-english/d/doc239196.html तद्य इह रमणीयचरणा अभ्याशो ह यत्ते रमणीयां योनिमापद्येरन्ब्राह्मणयोनिं वा क्षत्रिययोनिं वा वैश्ययोनिं वाथ य इह कपूयचरणा अभ्याशो ह यत्ते कपूयां योनिमापद्येरञ्श्वयोनिं वा सूकरयोनिं वा चण्डालयोनिं वा ॥ ५.१०.७ ॥
tadya iha ramaṇīyacaraṇā abhyāśo ha yatte ramaṇīyāṃ yonimāpadyeranbrāhmaṇayoniṃ vā kṣatriyayoniṃ vā vaiśyayoniṃ vātha ya iha kapūyacaraṇā abhyāśo ha yatte kapūyāṃ yonimāpadyerañśvayoniṃ vā sūkarayoniṃ vā caṇḍālayoniṃ vā || 5.10.7 ||
- Among them, those who did good work in this world [in their past life] attain a good birth accordingly. They are born as a brāhmin, a kṣatriya, or a vaiśya. But those who did bad work in this world [in their past life] attain a bad birth accordingly, being born as a dog, a pig, or as a casteless person.
This translation is provided by Swami Lokeswarananda . When I looked closely , I found 2 things of interest. 1)Shudra is not mentioned . 2) Word "yonim" can mean womb too . Now in 1st line of verse :- If "yonim" in 1st line of this verse means womb then "shudra yonim" should be present because Shudra women give birth too.So "yonim" here means "birth as". Interesting thing is in Sanatan Dharma there are 2 types of birth :- Natural , and Spiritual(upanayana ceremony). Also here specifically brahmins,kshatriyas and vaishyas( twice born) are mentioned. And if "yonim" here means natural birth , then it contradicts with Skanda Purana Vol.18 Book VI , Nagar Kanda , Chapter 239 , ( Efficacy of Adoration , Penance etc.) Verse 31-34 https://www.wisdomlib.org/hinduism/book/the-skanda-purana/d/doc502218.html . So based on above conclusions is it possible that here "yonim" means 2nd birth and not the natural birth (only in 1st line of the verse , 1st line ends befor bad birth desciption)?